1. Field of the Invention
The present invention relates generally to sports equipment. The present invention relates more particularly to equipment for the sport of snowboarding, and to safety devices used to prevent injury while snowboarding.
2. Background
Snowboarding is a winter sport that has gained in global popularity and is now commonly practiced at most ski resorts in the United States. Many Americans have already purchased equipment for snowboarding. This equipment usually includes a snowboard, snowboarding boots, and bindings to attach the snowboarding boots to the snowboard.
Two general types of snowboard bindings are owned by Americans today: “strap-in” snowboard bindings and “click-in” snowboard bindings. Both types of bindings are attached to the snowboard by threaded fasteners and are not removed from the snowboard during use. Neither type of binding is designed to separate from the snowboard under the force of a crash.
With strap-in bindings, the snowboarding boot is attached to the bindings by straps that must be connected and tightened. The straps must be loosened and/or disconnected to detach the snowboarding boots from the bindings. Strap-in bindings also serve to structurally reinforce the snowboarder's ankles while snowboarding (i.e. when the straps are tightened). Because the strap-in bindings provide the necessary rigidity around the snowboarder's ankles, the snowboarding boots need not be designed to be rigid or stiff. Therefore, the snowboarding boots that are designed to be compatible with strap-in bindings can be designed to be comfortable for normal walking. However, the feature facilitating comfortable boot design does not significantly enhance safety while snowboarding nor significantly reduce the chance of injury while snowboarding. Contemporary strap-in bindings are not designed to allow the separation of the boots from the snowboard under the force of a crash.
Click-in bindings better facilitate the intentional attachment and detachment of the snowboarding boots to and from the bindings. With click-in bindings, the snowboarding boots are specially designed or adapted to attach to the bindings, and detach from the bindings, upon a specific intentional action accomplished by the snowboarder. A snowboarder typically needs to detach one foot from the snowboard at the bottom of the ski slope to enable the snowboarder to push that foot against the snow for self-propulsion to the ski lift. The snowboarder must then reattach the disconnected foot to the snowboard after arriving at the top of the ski slope. Therefore, the ease of intentional detachment and reattachment can be an important performance characteristic of snowboard bindings. However, snowboarding boots that are specially designed to function with click-in bindings are typically very stiff because the boot must provide the ankle reinforcement necessary for snowboarding, without the additional structural support provided by strap-in bindings. Consequently such boots are less comfortable for walking than boots designed for use with strap-in bindings. Moreover, the feature facilitating intentional disconnection of the boots from the bindings does not significantly enhance safety nor significantly reduce the chance of injury. Contemporary click-in bindings are not designed to allow the separation of the boots from the snowboard under the force of a crash.
In contrast with snowboarding equipment, skiing equipment has evolved to include sophisticated safety release mechanisms in the bindings that attach ski boots to skis. These safety release mechanisms have prevented many ski-related injuries. However, such safety release mechanisms are absent in commercially available snowboarding equipment.
One reason why commercially available snowboard bindings have not yet evolved to include safety release mechanisms is the presence of at least one additional important design requirement: the need for simultaneous release of both bindings (one for each of the snowboarder's two feet) under the force of a crash. The release mechanisms that are typical of contemporary ski equipment do not satisfy that important design requirement. Therefore, there is a need for a practical safety release mechanism for snowboard bindings that can ensure simultaneous release of the bindings for both feet under the force of a crash. Furthermore, because of widespread fear among the purchasers of snowboarding equipment of the risk of injury associated with the release of only one snowboard binding and not the other, there is a commercial need for the safety release mechanism to provide clearly apparent and visually verifiable certainty in the simultaneity of the release.
Attempts have been made in the prior art to design a practical safety release mechanism for snowboard bindings. These designs seem to have been inspired by the safety release mechanisms developed for ski bindings, since their focus remains on the separation of each individual boot from all or part of its binding. The attempts have not contemplated a safety release that could separate standard snowboard bindings, including contemporary strap-in bindings, from the snowboard in response to the forces of a crash. Furthermore, prior art bindings for individual boots that release when that boot is twisted or lifted may not release when the snowboarder's entire trunk is twisted by the snowboard. When the torque applied by the snowboard to the snowboarder is about an axis normal to the snowboard, but is a torque about the longitudinal axis of the snowboarder's entire body rather than the twisting of an individual foot, prior art bindings for individual boots may perceive this torque as a lateral shear force in the plane of the snowboard and consequently may not release. Many snowboarders suffer injuries to their lower spine as a result of such torques. Thus, there is a need for a safety release mechanism that will release when a torque about an axis normal to the snowboard, but about the snowboarder's entire trunk rather than the twisting of an individual foot, exceeds a given threshold. Many prior art designs have been variants of click-in bindings that usually require the snowboarder to wear a specially designed or adapted boot. Many Americans have already purchased snowboard boots that they chose because of comfort, warmth, or style. Accordingly there is a need for a new safety release mechanism that will reduce the forces and torques applied to the snowboarder's legs and trunk during a crash, but will not render already-purchased snowboarding boots and bindings obsolete.